#region License
/*
* Copyright 2002-2008 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#endregion
using System;
using System.Messaging;
using System.Transactions;
using Common.Logging;
using Spring.Transaction;
namespace Spring.Messaging.Listener{
/// <summary>
/// A MessageListenerContainer that uses distributed (DTC) based transactions. Exceptions are
/// handled by instances of <see cref="IDistributedTransactionExceptionHandler"/>.
/// </summary>
/// <remarks>
/// <para>
/// Starts a DTC based transaction before receiving the message. The transaction is
/// automaticaly promoted to 2PC to avoid the default behaivor of transactional promotion.
/// Database and messaging operations will commit or rollback together.
/// </para>
/// <para>
/// If you only want local message based transactions use the
/// <see cref="TransactionalMessageListenerContainer"/>. With some simple programming
/// you may also achieve 'exactly once' processing using the
/// <see cref="TransactionalMessageListenerContainer"/>.
/// </para>
/// <para>
/// Poison messages can be detected and sent to another queue using Spring's
/// <see cref="SendToQueueDistributedTransactionExceptionHandler"/>.
/// </para>
/// </remarks>
public class DistributedTxMessageListenerContainer : AbstractTransactionalMessageListenerContainer
{
#region Logging Definition
private static readonly ILog LOG = LogManager.GetLogger(typeof (DistributedTxMessageListenerContainer));
#endregion
private IDistributedTransactionExceptionHandler distributedTransactionExceptionHandler;
/// <summary>
/// Gets or sets the distributed transaction exception handler.
/// </summary>
/// <value>The distributed transaction exception handler.</value>
public IDistributedTransactionExceptionHandler DistributedTransactionExceptionHandler
{
get { return distributedTransactionExceptionHandler; }
set { distributedTransactionExceptionHandler = value; }
}
/// <summary>
/// Set the transaction name to be the spring object name.
/// Call base class Initialize() functionality.
/// </summary>
public override void Initialize()
{
// Use object name as default transaction name.
if (TransactionDefinition.Name == null)
{
TransactionDefinition.Name = ObjectName;
}
// Proceed with superclass initialization.
base.Initialize();
}
/// <summary>
/// Does the receive and execute using TxPlatformTransactionManager. Starts a distributed
/// transaction before calling Receive.
/// </summary>
/// <param name="mq">The message queue.</param>
/// <param name="status">The transactional status.</param>
/// <returns>
/// true if should continue peeking, false otherwise.
/// </returns>
protected override bool DoReceiveAndExecuteUsingPlatformTransactionManager(MessageQueue mq,
ITransactionStatus status)
{
#region Logging
if (LOG.IsDebugEnabled)
{
LOG.Debug("Executing DoReceiveAndExecuteUsingTxScopeTransactionManager");
}
#endregion Logging
//We are sure to be talking to a second resource manager, so avoid going through
//the promotable transaction and force a distributed transaction right from the start.
TransactionInterop.GetTransmitterPropagationToken(System.Transactions.Transaction.Current);
Message message;
try
{
message = mq.Receive(TimeSpan.Zero, MessageQueueTransactionType.Automatic);
}
catch (MessageQueueException ex)
{
if (ex.MessageQueueErrorCode == MessageQueueErrorCode.IOTimeout)
{
//expected to occur occasionally
#region Logging
if (LOG.IsTraceEnabled)
{
LOG.Trace(
"MessageQueueErrorCode.IOTimeout: No message available to receive. May have been processed by another thread.");
}
#endregion
status.SetRollbackOnly();
return false; // no more peeking unless this is the last listener thread
}
else
{
// A real issue in receiving the message
lock (messageQueueMonitor)
{
mq.Close();
MessageQueue.ClearConnectionCache();
}
throw; // will cause rollback in surrounding platform transaction manager and log exception
}
}
if (message == null)
{
#region Logging
if (LOG.IsTraceEnabled)
{
LOG.Trace("Message recieved is null from Queue = [" + mq.Path + "]");
}
#endregion
status.SetRollbackOnly();
return false; // no more peeking unless this is the last listener thread
}
try
{
#region Logging
if (LOG.IsDebugEnabled)
{
LOG.Debug("Received message [" + message.Id + "] on queue [" + mq.Path + "]");
}
#endregion
MessageReceived(message);
if (DistributedTransactionExceptionHandler != null)
{
if (DistributedTransactionExceptionHandler.IsPoisonMessage(message))
{
DistributedTransactionExceptionHandler.HandlePoisonMessage(message);
return true; // will remove from queue and continue receive loop.
}
}
DoExecuteListener(message);
}
catch (Exception ex)
{
HandleDistributedTransactionListenerException(ex, message);
throw; // will rollback and keep message on the queue.
}
finally
{
message.Dispose();
}
return true;
}
/// <summary>
/// Handles the distributed transaction listener exception by calling the
/// <see cref="IDistributedTransactionExceptionHandler"/> if not null.
/// </summary>
/// <param name="exception">The exception.</param>
/// <param name="message">The message.</param>
protected virtual void HandleDistributedTransactionListenerException(Exception exception, Message message)
{
IDistributedTransactionExceptionHandler exceptionHandler = DistributedTransactionExceptionHandler;
if (exceptionHandler != null)
{
exceptionHandler.OnException(exception, message);
}
}
}
}
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